1. Field of the Invention
This invention relates to an automatic positioning apparatus for an automative vehicle to the used for automatically driving a vehicle mounted device into a memorized position suitable for the driver, and more particularly to a system and a method for controlling the attitude of the vehicle mounted device such as a seat, a steering wheel or the like, back and forth, up and down, for example.
2. Description of the Prior Art
Heretofore, there has been used an automatic positioning apparatus as shown in FIG. 11.
The automatic positioning apparatus 100 illustrated in the figure is so designed as to actuate a shaft 103 of a steering wheel 104 up and down between the upper position a and the lower position b through a tilt motor 102 and move the steering wheel 104 back and forth between the front side position c and the rear side position d by actuating the steering wheel shaft 103 telescopically through a telescopic movement motor 105 in accordance with a manual operation of a steering wheel positioning switch 101. The automatic positioning apparatus 100 is also designed so as to drive a seat 108 back and forth slidingly through a seat motor 109 in response to a manual operation of a seat positioning switch 110.
The tilt motor 102 and the telescopic movement motor 105 are connected with a controller 106 housed with a microcomputer through the steering wheel positioning switch 101, and the controller 106 is connected with a battery 107. The controller 106 is connected with the seat motor 109 through the seat positioning switch 110, and tilt data representing an inclination angle of the steering wheel shaft 103 detected by a tilt sensor 111, telescopic movement data representing a telescopic location of the steering wheel 104 detected by a telescopic movement sensor 112 and slide data representing a sliding location of the seat 108 detected by a seat sensor 113 are input to the controller 106 through an I/O interface circuit (not shown).
In case of memorizing driving positions suitable for a driver, the steering wheel shaft 103 is moved into the position e by actuating the tilt motor 102 and the steering wheel 104 is moved to the position f suitable for the driver by adjusting telescopic location of the steering wheel shaft 103 through the telescopic movement motor 105 according to the manual operation of the steering wheel positioning switch 101, and the seat 108 is moved slidingly into the position g suitable for the driver by actuating the seat motor 109 according to the manual operation of the seat positioning switch 110. In this state, the controller 105 memorizes the position e detected by the tilt sensor 111, the position f detected by the telescopic movement sensor 112 and the position g detected by the seat sensor 113 as the driving positions suitable for the driver in response to a presetting operation of a set switch (not shown) disposed on a switch board together with the seat positioning switch 110.
After this, the steering wheel 104 and the seat 108 move automatically to the respective positions e, f and g memorized by the controller as the driving positions suitable for the driver by actuating the tilt motor 102, the telescopic movement motor 105 and the seat motor 109 according to a positioning operation of the set switch.
Additionally, in the automatic positioning apparatus 100, electric currents are supplied to the tilt motor 102, the telescopic movement motor 105 and the seat motor 109 so as to actuate the steering wheel 104 and the seat 108 toward turnout positions by sensing an ignition key (not shown) to be pulled out from an ignition switch, sensing a door on the driver's seat side to be opened in case the ignition key is inserted into the ignition switch, or sensing the ignition key to be turned to the OFF-position from the ACC-position in the ignition switch in case the door is opened when the steering wheel positioning switch 101 is switched into the automatically operable state. Whereby, the shaft 103 of the steering wheel 104 is moved from the position e to the upper position a (turnout position) by the tilt motor 102, the sterring wheel 104 is moved from the position f to the front side position c (turnout position) by the telescopic movement motor 105, and the seat 108 is moved from the position g to position h (turnout position) shifted backwardly from the position g by predetermined distance after the positions where the steering wheel 104 and the seat 108 are at present (position e, position f and position g in this case) are memorized in the microcomputer of the controller 106. Therefore, the space between the steering wheel 104 and the seat is made wider, and it becomes easy to get in and out from the driver's seat of the automative vehicle.
At the state in which the steering wheel 104 and the seat 108 are in the turnout position, if the ignition key is inserted into the ignition switch, the door is closed when the ignition key is inserted into the ignition switch or the ignition key is turned to the (ON-position from the ACC-position in the ignition switch when the door is opened, electric currents are supplied to the tilt motor 102, the telescopic movement motor 105 and the seat motor 109 so as to actuate the steering wheel 104 and the seat 108 toward the previous positions memorized in the microcomputer of the controller 106 immediately before the steering wheel 104 and the seat 108 are actuated to the turnout positions. Whereby the steering wheel shaft 103 is moved from the turnout position a to the position e by the tilt motor 102, the steering wheel 104 is moved from the turnout position c to the position f by the telescopic motor 105 and the seat 108 is moved slidingly from the turnout position h to the position g by the saeat motor 109. In such a manner, the steering wheel 104 and the seat 108 return automatically to the positions memorized immediately before starting to the turnout positions, that is, the originally memorized positions e, f and g.
On the other side, in a case of actuating the steering wheel 104 or the seat 108 by manual operation while the vehicle is travelling for example, the automatic positioning apparatus 100 is so designed as to inch the motors so as not to obstruct the safety driving.
Namely, when the steering positioning switch 101 is switched on in the upward direction at time i as shown in FIG. 12 for example, an electric current is supplied to the tilt motor 102 in the forward rotational direction, thereby rotating the tilt motor 102 in the forward direction and actuating the steering wheel shaft 103 upwardly.
After the predetermined time, an electric current is supplied to the tilt motor 102 in the reverse rotational direction according to a downward signal output from the controller 106 at time j shown in the figure, whereby the tilt motor 102 stops by dynamic braking becasue the tilt motor 102 is supplied with the electric current in the forward rotational direction according to the manual operation of the steering wheel positioning switch 101 and the electric current in the reverse rotational direction according to the downward driving signal output from the controller 106 at the same time. Then the controller 106 discontinues to output the downward signal by sensing the steering wheel positioning switch 101 to be changed off, thereby shutting off the electric current in the reverse rotational direction to the tilt motor 102.
In such a manner, the motors are so designed as to be inched in the automatic positioning apparatus 100.
However, there is the possibility that the steering wheel 104 and the seat 108 pass over the memorized driving positions by inertia even if the power supply to the motors (tilt motor 102, telescopic motor 105, seat motor 109 and the like) is cut off at the time of the return to the memorized driving positions according to the positioning operation of the set switch.
Therefore, there is a problem since the steering wheel 104 and the seat 109 stop at the positions deviated from the proper driving positions memorized by the controller 106.
Additionally, if the presetting operation of the set switch is done in this time, there is another problem in that the positions deviating from the proper driving positions are newly memorized in the controller 106 as driving positions in spite that the driver does not have an intention to change the memorized driving positions. Where the driver repeats to get in and out from the driver's seat many times, there is also a problem in that the difference between the returning positions and the originally memorized driving positions gradually increases because the returning positions memorized in the controller 106 are renewed every time the driver gets out the vehicle and the steering wheel 104 and the seat 108 are actuated toward the turnout positions.
Furthermore, if the positioning operation of the set switch is done again after the steering wheel 104 and the seat 108 return toward the memorized driving positions according to the positioning operation of the set switch and stop once, the steering wheel 104 and the seat 108 are moved in the opposite direction because the steering wheel 104 and the seat 108 stop at the positions deviated from the memorized driving positions. Therefore, there is a problem since the driver is uncomfortable.
In addition to above, in case of manually actuating the steering wheel 104 or the seat 108 while the vehicle is travelling, the steering wheel 104 or the seat 108 is so designed as to be acutated by inching the tilt motor 102, the telescopic movement motor 105 or the seat motor 109 under the aforementioned control. However, as shown in FIG. 12, a time lag may be caused until the electric current in the reverse rotational direction is cut off after changing off the steering wheel positioning switch 101 at time k shown in the figure because the control needs some time to sensing the steering wheel positioning switch 101 to be changed off and to actuate a relay for cutting off the electric current to the tilt motor 102.
Accordingly, there is another problem in that the steering wheel 104 is actuated over again in the downward direction after moving in the upward direction and the driver feels displeasure because the electric current in the reverse rotational direction continue to be supplied to the tilt motor 102 for a short time even after the electric current in the forward rotational direction is cut off according to the manual operation of the steering wheel positioning switch 101.